It is known that bundling-up or association of containers into unitary packages, in particular beverage containers such as bottles, cans, jars, is presently carried out by packaging elements or "clusters" made of injected or thermoformed plastics or paperboard material generally decorated in advance.
In particular, for packaging 1 liter and bigger bottles into a unitary set, a heat-shrinkable plastics membrane or film is used, a support handle being formed therein or added thereto, which handle is for example made of a strip surrounding the unitary set and passing under it.
In some packages, in addition to plastics membranes, the use of paperboard holding bowls into which the container bottoms are introduced, is also provided.
However, the known bundling-up technique as briefly described above has some limits and inconveniences.
In fact, in case of packages completely or partly made of paperboard material, not only possible wear of the material due for example to dampness and to the weight of the material itself may occur, but also manufacturing costs to be borne are rather high.
As regards packages made of heat-shrunk film, in addition to the important amount of material needed for each unitary set, a non negligible energy consumption is also required due to the heat workings for applying the film.
Furthermore, inscriptions or messages, such as advertisements, cannot be put on said heat-shrunk films, as, on the one hand, they would be deformed due to the material shrinkage during the packaging process and, on the other hand, it would be difficult to position them properly on the packages.